#pragma once

#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include "Log.hpp"
#include "Thread.hpp"
#include "Cond.hpp"
#include "Mutex.hpp"

//.hpp header only

namespace ThreadPoolModule
{
    using namespace ThreadModlue;
    using namespace LogModule;
    using namespace CondModule;
    using namespace MutexModue;
    
    static const int gnum = 5;

    template<typename T>
    class ThreadPool
    {
    private:
        void WakeUpAllThread()
        {
            LockGuard lockguard(_mutex);
            if(_sleepernum)
                _cond.Broadcast();
            LOG(LogLevel::INFO) << "唤醒所有的休眠线程";
        }

        void WakeUpOne()
        {
            _cond.Signal();
            LOG(LogLevel::INFO) << "唤醒一个休眠线程";
        }

        ThreadPool(int num = gnum): _num(num), _isrunning(false), _sleepernum(0)
        {
            for(int i = 0;i < num;i++)
            {
                _threads.emplace_back(
                    [this](){
                        HandlerTask();
                    }
                );
            }
        }

        void Start()
        {
            if(_isrunning)
            {
                return;
            }
            _isrunning = true;
            for(auto& thread:_threads)
            {
                thread.Start();
            }
        }
    
        ThreadPool(const ThreadPool<T>&) = delete;
        ThreadPool<T>& operator=(const ThreadPool<T>&) = delete;

    public:

        static ThreadPool<T>* GetInstance()
        {
            if(inc == nullptr)
            {
                LockGuard lockguard(_lock);

                LOG(LogLevel::DEBUG) << "获取单例对象...";
                if(inc == nullptr)
                {
                    LOG(LogLevel::DEBUG) << "首次使用单例，创建...";
                    inc = new ThreadPool<T>();
                    inc->Start();
                }
            }

            return inc;
        }

        void HandlerTask()
        {
            char name[128];
            pthread_getname_np(pthread_self(), name, sizeof(name));
            while(true)
            {

                T t;
                {
                    LockGuard lockguard(_mutex);
                    while(_taskq.empty() && _isrunning)
                    {
                        _sleepernum++;
                        _cond.Wait(_mutex);
                        _sleepernum--;
                    }

                    //内部的线程被唤醒
                    if(!_isrunning && _taskq.empty())
                    {
                        LOG(LogLevel::INFO) << name << "线程池退出 && 任务队列为空";
                        break;
                    }

                    //一定有任务
                    t = _taskq.front();
                    //从q中获取任务，任务已经是线程私有的了
                    _taskq.pop();
                }

                t();//处理任务
                // sleep(1);
                // LOG(LogLevel::DEBUG) << name << "is running hello mihayou";
            }
        }

        void Stop()
        {
            if(!_isrunning)
            {
                return;
            }

            _isrunning = false;

            //唤醒所有线程
            WakeUpAllThread();
        }

        void Join()
        {
            for(auto& thread:_threads)
            {
                thread.Join();
            }
        }

        bool Enqueue(const T& in)
        {
            if(_isrunning)
            {
                LockGuard lockguard(_mutex);
                _taskq.push(in);

                if(_threads.size() == _sleepernum)
                {
                    WakeUpOne();
                }
                return true;

            }
            return false;
        }

        ~ThreadPool()
        {

        }

    private:
        std::vector<Thread> _threads;
        int _num;//线程池中，线程的个数
        std::queue<T> _taskq;
        Cond _cond;
        Mutex _mutex;

        bool _isrunning;
        int _sleepernum;

        //懒汉模式
        static ThreadPool<T>* inc;//单例指针
        static Mutex _lock;
    };

    template<typename T>
    ThreadPool<T>* ThreadPool<T>::inc = nullptr;
    //单例模式
    template<typename T>
    Mutex ThreadPool<T>::_lock;
}